If you are interested in purchasing a pair of circular needles that are good quality, not too round on the tips, and not too expensive...get yourself a pair of KnitPicks Harmony needles. They can be purchased needle by needle, piece by piece...and by the set with almost all the sizes. Depends on your budget.
ALSO, the yarn at KnitPicks isn't too expensive, and all of it is great yarn.
I have their Harmony (the swirl-multi-colored wood, and the nickel plated OPTIONS...they are both wonderful) and would recommend them to a new knitter. Wood is easier for a new knitter to control IMO.
They have a TRY IT Needle setthat has all three types of their interchangeable needles in the set: Harmony, Nickel and Acrylic. $19.99